Introduction
Looking for a classic American springtime treat that’s buttery, tangy, and just the right amount of sweet? These homemade Rhubarb Bars hit all the right notes. They feature a melt-in-your-mouth shortbread crust, a soft and jammy rhubarb layer, and a golden crumb topping. Perfect for picnics, potlucks, or a cozy dessert at home.
Whether you grow rhubarb in your backyard or pick it up at the farmer’s market, this bar recipe makes the most of its tart flavor — balanced with a bit of sugar and warm vanilla. It’s simple, nostalgic, and loved across generations.
Ingredients
For the Shortbread Base:
- 1 cup (2 sticks) unsalted butter, melted
- 1/2 cup granulated sugar
- 1/4 tsp salt
- 2 cups all-purpose flour
For the Rhubarb Filling:
- 3 cups chopped rhubarb (fresh or frozen, thawed and drained)
- 3/4 cup granulated sugar
- 2 tbsp cornstarch
- 1 tsp vanilla extract
- Juice of 1/2 lemon
For the Crumb Topping:
- 1/2 cup rolled oats
- 1/2 cup all-purpose flour
- 1/3 cup light brown sugar
- 1/2 tsp ground cinnamon
- 1/4 cup cold butter, cubed
Instructions
Step 1: Prep the Oven and Pan
Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish or line it with parchment paper for easy removal later.
Step 2: Make the Shortbread Crust
In a bowl, combine melted butter, sugar, salt, and flour. Mix until a soft dough forms.
CookWithKushal Tip: Use melted butter instead of cold for a more tender, chewy base instead of a dry one — especially great for rhubarb’s juicy filling.
Press the dough evenly into the prepared baking dish. Use the back of a measuring cup to flatten and smooth it out.
Bake the crust for 15 minutes or until just lightly golden. Set aside to cool slightly.
Step 3: Prepare the Rhubarb Filling
In a saucepan over medium heat, add chopped rhubarb, sugar, cornstarch, vanilla, and lemon juice. Stir frequently until rhubarb softens and the mixture thickens, about 10–12 minutes.
CookWithKushal Tip: If using frozen rhubarb, drain excess liquid before cooking to avoid a soggy filling.
Remove from heat and let it cool for 5 minutes.
Step 4: Spread the Filling
Pour the rhubarb mixture over the pre-baked shortbread base and spread evenly with a spatula.
Step 5: Make the Crumb Topping
In a bowl, mix together oats, flour, brown sugar, and cinnamon. Add cold butter cubes and rub with your fingers or a pastry cutter until crumbly.
Sprinkle the topping generously over the rhubarb layer.
Step 6: Bake Until Golden
Return the pan to the oven and bake for another 30 minutes, or until the top is golden brown and the filling is bubbly.
Step 7: Cool & Slice
Allow the bars to cool completely in the pan. For clean slices, refrigerate for 1 hour before cutting.
CookWithKushal Tip: Serve chilled for a firm, cookie-like bite — or warm with vanilla ice cream for an indulgent dessert.
Storage Instructions
Store leftover rhubarb bars in an airtight container at room temperature for 2 days, or in the refrigerator for up to 5 days. They also freeze well for up to 2 months.
Why You’ll Love This Recipe
- Perfect balance of tart & sweet
- No mixer needed
- Kid-friendly and lunchbox-approved
- Great make-ahead treat for spring & summer events
CookWithKushal (Chef) Tip Round-up
- Melted butter = chewier crust
- Lemon juice enhances tartness
- Drain frozen rhubarb to avoid watery filling
- Chill before slicing for neater bars